THIS. DeepSkull is dead on here with the cheap indicators and expensive indicator holders. I've got both expensive and cheap indicators. And I've got both cheap and expensive holders. On a little hobby machine (and especially when starting out in machining) you won't often see a difference in cheap and expensive indicators. You will definitely see a difference in cheap and expensive indicator holders.

I've used a few, and NOGA's are my favorites. The longer the arm, the better. I also prefer having a fine adjustment on the base and not on the arm. Doesn't wobble while you adjust it if its on the base.

Something like this: https://www.amazon.com/NOGA-Standard-Holder-Magnetic-Base/dp/B001VY07VQ/ref=sr_1_5?ie=UTF8&qid=1494561300&sr=8-5&keywords=noga+indicator+holder

https://www.amazon.com/gp/product/B001VY07VQ/

$87.99 + $8.16 shipping on amazon (ha I bought this one when it was amazon prime eligible). I use it every day

Oh I just saw you said 2 fine adjustments...